Pipetting aid devices comprising a microtiter plate support or a test tube support plate are known that comprise an array of light elements such as light emitting diodes, and means for controlling these light elements, for example, formed from control keys and/or buttons. These devices are usually designed to hold microtiter plates with standard dimensions comprising an array of wells, the number of which is generally a multiple of 6 wells per row and 4 wells per column. Thus, in example embodiments, plates with 24×16 (384) wells and plates with 12×8 (96) wells are used.
The layout of wells on typically used microtiter plates varies as a function of the number of wells in these plates. The array of wells relative to the edges of the plate is offset from one plate to another, depending on the number of wells in each plate. The diameter of the well section can also vary from one type of plate to another. Thus, plates comprising a relatively small number of wells can contain wells with a larger cross-section than wells in plates comprising a larger number of wells.
To operate satisfactorily, a pipetting aid device of the type described has a light element or an arrangement of light elements facing each well in the microtiter plate that it supports. Consequently, microtiter plates are associated with assembly adaptors if they have to be installed on known pipetting aid devices. More precisely, each type of microtiter plate is characterized by the arrangement of wells in the plate, and is commonly used with an adaptor comprising:
a lower face provided with means designed to cooperate with centering means supported on pipetting aid device supports;
an upper face comprising plate centering means, arranged to enable an alignment of wells in plates of the type associated with this adaptor, with at least some of the light elements of pipetting aid devices; and
a array of orifices that connect the lower face to the upper face of the adaptor and that are intended to allow light emitted by light elements of the pipetting aid devices to reach the wells of the microtiter plates.
However, the change of the adaptor that must accompany each change in the type of microtiter plate is tedious for the user. Furthermore, a set of adaptors associated with each plate in a given set of microtiter plates is required which introduces a major extra cost and is not very practical.